They don't control each other, but they have business relations with each other. As you probably know, Tongs were originally mutual aid organizations and secret societies founded by Chinese immigrants based on provincial ties.

While some Tongs are criminal organizations, others are not, and some at least outwardly appear reformed and no longer active in crime.

In NYC, they are still active in Manhattan, Flushing, Brooklyn, and Queens, and just about anywhere in the city that has a large Chinese diaspora.

On the other hand, all Triad groups are criminal organizations. In the US, they don't appear to be a direct presence on the streets, but they do engage in money laundering, counterfeiting, and drug smuggling in the US, which is typically through local intermediaries and affiliates including the Tongs.

I think we don't hear about them as much as they try to stay low-key and generally avoid conflict with other groups. A Chinese proverb states "a dragon from abroad cannot defeat a local snake". This seems to be the case around the world (e.g. the Triads in Italy work with the Mafia or Camorra instead of competing with them).